kernel: mm,hugetlb: take hugetlb_lock before decrementing h->resv_huge_pages

In the Linux kernel, the following vulnerability has been resolved: mm,hugetlb: take hugetlblock before decrementing h-resvhugepages The h-hugepages counters are protected by the hugetlblock, but allochugepage has a corner case where it can decrement the counter outside of the lock. This could le...